Prostate problems, such as benign prostate hyperplasia (BPH) and malignant prostate cancer, are common occurrences among older men. The effects of these diseases are generally accompanied by swelling or enlargement of the prostate gland. Apart from the life-threatening aspects of malignant prostate cancer, the everyday symptoms and effects of these diseases are usually troublesome. One such problem relates to the ability to control and achieve normal urine discharge. When the prostate gland enlarges to the extent that the prostatic urethra, the part of the urinary tract which extends through the prostate gland, becomes obstructed or restricted, considerable difficulties arise in discharging urine at will. Such difficulties are typically referred to as urinary tract retention. Urinary tract retention can be either acute or chronic.
Surgical treatments are available for relieving urinary tract retention problems. Those treatments include microwave thermotherapy and transurethral resection of the prostate (TURP). Microwave thermotherapy and some other heat treatments involve heating the prostatic urethra and surrounding prostate tissue to such an extent that the tissue is destroyed. Thereafter, the destroyed tissue sloughs off or is absorbed in the body, resulting in an enlargement of the urinary tract through the prostate gland. The enlargement of the urinary tract through the prostate gland eliminates or relieves the obstruction or restriction and permits better urine flow. A TURP procedure involves surgically resecting tissue from the prostate gland to eliminate or reduce obstruction or restriction.
Both thermotherapy and TURP surgical procedures cause temporary side effects, for example inflammation and swelling of the prostate. The side effects usually require the patient to use an indwelling drainage catheter for a few days up to several weeks following the procedure to permit urination while the swelling subsides and the tissue of the prostate gland heals or stabilizes. The tissue of the prostate gland which remains viable after the thermotherapy or TURP procedure is quite raw and tender, and direct contact from urine can aggravate the inflammation and increase the risk of infection. An indwelling catheter permits the urine to pass through the tissue where the surgical procedure was performed with only minimal contact to the treated tissue.
In those cases where the diseased prostate gland cannot be treated with thermotherapy or a TURP procedure, the obstruction or restriction may become so significant that normal urinary functions are not possible or are only possible with great difficulty. In these circumstances, it is necessary for a catheter to be used for the rest of the patient's life. In some cases, the patient is taught to insert a full-length catheter whenever urination is necessary. In other cases where the patient cannot insert a full-length catheter himself, the full-length catheter is inserted in the urinary tract and remains in place until removed by medical personnel.
The typical type of urinary catheter used while the prostate gland heals, or on a continual basis, is a full-length urinary catheter. A full-length urinary catheter extends from the exterior of the patient through the entire length of the urinary tract into the bladder. A clamp or other mechanical valve is attached at the exterior of the full-length urinary catheter, and the clamp is opened to void the urine from the bladder. Sometimes a reservoir is also attached to the end of the full-length catheter to collect the urine discharge. The urinary sphincter muscle, which normally controls the flow of urine from the bladder, is no longer able to perform its natural function of constricting the urethra to control urine flow because the full-length urinary catheter provides a continuously open flow path for the urine. The urinary sphincter muscle is not able to constrict the flow path through the full-length urinary catheter.
In addition to the patient lacking the ability to naturally control urine flow, the existence of the full-length urinary catheter extending out of the urinary tract, and presence of the clamp and the reservoir cause discomfort and are awkward to deal with and embarrassing for the patient. The full-length urinary catheter may create limitations from a social standpoint and almost always creates a variety of quality of life issues which must be confronted. Sexual activity is impossible. An increased risk of infection also results.
Because of the quality of life and social issues associated with full-length urinary catheters, partial-length indwelling catheters have been developed. Partial-length indwelling catheters typically extend only from the bladder through the prostate gland, and not along the entire length of the urinary canal through the penis to the exterior of the body. The reduced length permits the urinary sphincter muscle to control urine flow more naturally, while still bypassing most of the urine flow around the swollen or raw prostate gland. No sizeable part of the catheter extends out of the urinary canal at the penis.
Keeping a partial-length indwelling catheter in the proper position is essential. The short length may allow the catheter to move completely into the bladder or move out of the prostatic urethra into the urinary canal. Either type of unintended movement may require serious medical intervention to correct.
A partial-length urinary catheter typically uses an inflatable balloon at its distal end to prevent the catheter from withdrawing from the bladder and moving out of the prostatic urethra and into the urinary canal. However, the balloon cannot prevent the partial-length urinary catheter from moving into the bladder and thus out of the prostate gland and urethra.
One way of preventing a partial-length urinary catheter from moving into the bladder involves attaching a relatively short and rigid anchor tube to the partial-length catheter with a short length of thread-like material. The anchor tube is approximately as large in diameter as the catheter. The catheter and the anchor tube are positioned in the urinary canal on opposite sides of the urinary sphincter muscle. The thread-like material extends through urethra of the urinary sphincter muscle. The urinary sphincter muscle is able to constrict around the thread-like material to stop urine flow and is able to dilate to permit the flow of urine, in a natural manner. The anchor tube is hollow to pass the discharged urine through the urinary canal. By positioning the anchor tube on the opposite side of the urinary sphincter muscle from the partial-length catheter within the prostatic urethra, the normal constricted state of the urinary sphincter muscle adjacent to the anchor tube prevents the partial-length catheter from moving into the bladder.
Another type of partial-length urinary catheter substitutes a three-dimensionally shaped anchor element for the anchor tube. The anchor element is also connected to the partial length urinary catheter by a tether-like thread. The three-dimensional anchor element is located within the urinary canal proximal of the urinary sphincter muscle, and the tether-like thread extends through the urethra within the urinary sphincter muscle to make natural control over urination possible.
Inserting and removing the rigid tube or three-dimensional anchor element along with the partial-length urinary catheter may be difficult or painful. Special types of insertion tools and techniques are required to use partial-length urinary catheters with rigid tube and three-dimensional anchor elements.
Because the partial-length prostatic urinary catheter must be inserted with the balloon deflated, all such balloon catheters must have some provision for inflating the balloon after the proper position of the catheter is attained. To inflate the balloon, a conduit or channel for adding fluid to the balloon must extend from the balloon to the exterior of the urinary tract. In a related context, the balloon must be deflated to remove the urinary catheter. Typically the balloon is deflated by opening a valve attached to the catheter. Opening the valve allows the fluid to escape from the balloon, so that the catheter can thereafter be removed. Should the valve not open when intended, medical intervention is required to deflate the balloon.
Another difficulty is that the inflated balloon may slowly lose the inflation fluid. Such fluid loss may arise because the valve which confines the fluid to the balloon does not seal completely or because of slight pinhole breaches in the structural materials which form the balloon or seal it to the partial-length prostatic catheter. The risk of fluid loss is exacerbated because of the relatively lengthy time that the partial length urinary catheter remains in use, typically a few weeks. Longer use times provide a greater opportunity for balloon deflation. Any attempt to reinflate a balloon will generally require some form of medical intervention.
These and other considerations and disadvantages of previous indwelling catheters and their use have led to the improvements of the present invention.